/* 配色方案 */
/* 主色调:#0172b0 */
/* 次色调:#88daf7 */
/* 阴影色:#01517d */

*{
    margin:0;
    padding:0;
}

body{
    min-height: 100vh;
    /* background: url("../images/bg.jpg") no-repeat center/cover */
}

.container{
    /* 使container居中 */
    position: absolute;
    left:50%;
    top: 50%;
    transform: translate(-50%,-50%);

    width:350px;
    height: 240px;
}


.container .front,
.container .back{
    /* 使front和back重叠 */
    position: absolute;
    
    width: 100%;
    height: 100%;

    background: linear-gradient(25deg,#0172b0,#88daf7);
    box-shadow: 6px 6px 14px #01517d,inset 0 0 15px #88daf7;

    display: flex;
    flex-direction: column;

    transition: .5s cubic-bezier(0.48,-0.56, 0.51, 1.67);
}

.container .front{
    /* 让front显示在前 */
    z-index: 1;
}

.turn{
    margin: 10px;
    text-align: right;
}

.turn i{
    font-weight: bold;
    cursor: pointer;
}

h2,h4{
    margin: 10px 0;
    color:white;
    text-align: center;
    text-transform: uppercase;
}

.links{
    margin: 35px;

    display: flex;
    justify-content: space-between;
}

.links a{
    text-decoration: none;
}

.links i{
    color:white;
    font-size: 1.5rem;
}

.container .back{
    transform: rotateY(180deg);
}

.back.back-turn{
    transform: rotateY(0deg);
}

.front.front-turn{
    z-index: 0;
    transform: rotateY(-180deg);
}